Cabinet for exhibiting eye-testing devices.



J. M...'J0H NNNNN VCABIIWL POR BXHIBITING EYE TESTING DE VVVV s.

l l MNH '17 @i Hlm E v l l [4 N0.728,112. PATENTBD 11111112.1903.

J. 1v1. JOHNSTONr 1 l CABINET T011J EXHIBTTING BYE TESTING DENIC-Es.

' APPLIGA'TION FILED JULY 17. 1901.

N0 MODEL. 2 SHEETS-SHEET 2.

No. l728,112.

UNTTEED STATES Patented May 12, 1903.

. PATENT OFFICE.

JOHN MILTON JOHNSTON, OF CHICAGO, ILLINOIS.

CABINET FOR EXHIBITING*EYEQTESTINGPEVICES.

SPECIFICATION forming part of Letters Patent No.'72`8,11l2, dated May 12, 1903. Appiiauon fuea any 17. 190i. serai No. 68.612. (No model.)

refractive and muscular deficiencies ofV the eyes. Y

The main object of my invention is the provision of a cabinet for this purpose, which is very simple, durable, and inexpensive Ain construction and thoroughly efficient and practical in use.

To attain the desired objects, my invention consists of a cabinet for exhibiting eyetesting devices, embodying novel features of construction and combination of parts, substantially as disclosed herein'.

In the drawings, Figure l is a front elevation of the cabinet. Fig. 2 is a vertical central sectional view thereof. Fig. 3 is a view of the device with the Vfront removed.

Referring to the drawings, the numeral l designates a casing, which may be in rectangular form; but I prefer to make'it in the form of a clock. Placed upon the lower front portionof this casing are the series of dots 2,

the dots to the left of the center being print-V ed in black ink and the dots to the right ofAA the center being printed in red ink,"each` dot having numerals or letters or other characters 3 printed over them. The letters or gures or numerals printed over the red dots are to be printed in black ink and those printed over the black dots are to be printed in red ink.

Secured to the sides la of the cabinet at their front ed ges is a strip 2, provided with a central opening 2b for the receptionv of the forward journal of the'shaft`4. The rear end of the shaft 4 is mounted vin the opening 4a in the rear, 5 ofthe cabinet.

Mounted upon the shaft 4c and revoluble therewith is a dial or circular disk 5, which has the index or pointer 6 revoluble also therewith,said dial being observable through the circular opening 6a in the front of the cabinet. Placed upon the face of the casing in the segmental or semicircular'recess or groove 6b above and surrounding the upper half of the dial is the segment f1', provided with one hundred and eighty equal divisions, numbered from one to one hundred and eightyfrom left to right. 'Formed in the upperfront of the case abovethis scale is the rectangular Opening 8, through which are adapted to be seen letters or numbers carried uponfa transparent belt` or band 8a, passed behind this openingby means of the rollers 9, which are ju'rnaled inthe bearings 10 in the sides lof the casing. A light Il is employedlto'cause thelettersto be plainly seen and may be in the casing or in any convenient position outside. I employ pulleys 12 to revolve the rol1ers,which may be operated by the operator at any desired position. I also provide a pulley 13 upon the shaft 1l in order that the samemay'be-revolved -by the operator from any desired position;

From this construction it will be seen that I provide the dial generally used in testing eyes for astigmatism and the dots and figures upon the lower face ofthe casing for the prism test, while the revolving letters and numbers will facilitate the determination of the condition of the eyes. AThe prism: test is put into operation simply byhaving the patient try to observe the dots and numeralsV through a prism, which is'placed inthe patients hand. If the dots and numerals appear commingled orindistinct', the eyes'are affected; otherwise they are normal. j u

With;this device the eyes maybe tested and the proper remedy may be discovered, as the cause of the trouble may be readily ascertained by employing this device.

It is evident that I provide a cabinet for exhibiting eye-testing devices which is very simple, durable, and inexpensive in construction as well as thoroughly efficient tical in use. f

This cabinet has the advantage of enabling the operator to employ test-letters in single lines without confusing the patientwith the presence of other tests.

What I claim, and desire to secure by Letters Patent, is-

The herein-described cabinet for eye-testand rfa@- ing devices, comprising a bese, front sides, a, rear wall rising therefrom, a strip connected to the sides near their front edges and opposed to the rear of the front in the lower portion of the cabinet, said front Wall being provided with aJ rectangulaiopening in the upper portion thereof, a circular opening in the lower portion thereof and e segmental recess surrounding the upper circumference of the circle, a segmental strip mounted in seid recess, a shaft mounted in the rear and in the strip opposed to the front of the casing and having its ends extending beyond 'the rear and said strip, :t circuler disk carried upon the front end of said shaft and adapted to revolve Within the circuinropening of the front, a pair of shafts mounted in the sides in the upper portion of the cabinet, and a, belt carried by said shafts and adapted to have a portion of the body thereof exposed through the rectangular opening of the front.

In testimony whereof I affix my signature in presence of two Witnesses.

JOHN MILTON JOHNSTON.

Witnesses:

DAISY P. MATTHEWS, G. ALBERT MCCOLLUM. 

